Location determining techniques, such as GPS, cellular signal triangulation, or forward link timing, may be used to determine the location of a mobile device. Such a location determining technique may work well when a signal is available from an appropriate number of satellites or cellular towers, such as three. However, if the mobile device cannot receive a signal from the appropriate number of satellites or cellular towers, the position of the mobile device may not be able to be determined using the location determining technique. For example, when a mobile device is located within a structure, such as a building, it may be difficult to consistently (or even sporadically) use a GPS-based location determining technique due to interference to signals caused by the structure and/or objects within the structure. As such, determining a position within the structure using the mobile device may not be possible if GPS or cellular signals are the only available location determining technique.